Oil-in-water (O/W) or Water-in-oil (W/O) emulsions are well known in the field of cosmetics and dermatology, in particular for the preparation of cosmetic products, such as milks, creams, tonics, serums or toilet waters. In particular, a fine emulsion such as an O/W nano- or micro-emulsion is particularly interesting in cosmetic products due to its transparent or slightly translucent aspect.
For example, JP-A-H09-110635 discloses a fine emulsion which is formed by using a combination of polyglyceryl fatty acid ester, as a surfactant, and C10-C22 2-hydroxy fatty acid. In addition, JP-A-H11-71256 discloses a fine emulsion which is formed by using a combination of polyglyceryl fatty acid ester and a betain.